1. Field of the Invention
The present invention relates to MUX and DEMUX circuits using a photo gate transistor utilizing a field emission process adapted to emit electrons by applying an electric field between two adjacent electrodes in a vacuum or gas, such as the atmosphere, and a photoelectric effect adapted to emit electrons by irradiating photons with at least critical energy onto the surface of a particular material layer.
2. Description of the Prior Art
The recent development of electronic devices capable of achieving a high-speed operation, high integration and high reliability is based on the development of the physics relating to solid semiconductors. Such a demand on high-speed operation, high integration and high reliability is continuously increasing.
However, the development of such electronic devices has reached the limit of ultra-microprocessing techniques. As a result, various problematic factors are exhibited.
In particular, the conduction phenomenon of electrons occurring in a solid electronic device is determined by a scattering phenomenon of electrons resulting from electrons striking against grains in the solid electronic device. Accordingly, the mobility of electrons which is indicative of the degree of the conduction phenomenon is a very important physical quantity.
For this reason, electron mobility became the factor for determining electrical characteristics of semiconductor devices and materials of those semiconductor devices.
In the case of transistors using a silicon substrate, the mobility of electrons and holes in the silicon substrate is fixedly determined. As a result, the performance of such transistors is fixedly determined.
FIG. 1 is a sectional view illustrating a typical MOSFET as a conventional solid electronic device. This MOSFET includes a gate electrode 1, a source 2, a drain 3, a gate insulating film 4 and a silicon substrate 5.
In accordance with the operation principle of the MOSFET shown in FIG. 1, the greater part of the silicon substrate 5 serves only as a support. Actually, the movement of electrons is carried out in a channel induced in a portion of the silicon substrate disposed beneath a gate insulating film.
Also, the operation speed of the MOSFET is determined by the mobility of electrons in the silicon substrate 5.
As a result, MUX/DEMUX circuits using such a solid electronic device have a problem in that the limit of the high-speed operation is determined by the characteristic of the solid electronic device.